The challenge on all dairy farms is not about “can the farm generate more energy than is consumed” but rather “how to deal with the peak loadings of the twice daily milking”. There are several options- first is to store the energy generated either in batteries or in say hot water or ice. The technology for batteries is not yet efficient enough but it’s an area of intense worldwide research. http://www.therenewableenergycentre.co.uk/ http://www.decc.gov.uk/
The obvious solution is to reduce peak demand. First you should be installing a Smart meter to monitor existing power consumption. Ask your electricity supplier http://www.electricityprices.org.uk/free-smart-meters/
Next you need to investigate the technologies that are already being used successfully by other dairy farmers eg Varivac systems. http://www.corkillsystems.co.nz/ Every parlour is different but generally with the oil vane type pumps that are predominant in the UK, savings are around 75% of power usage on the pumps themselves, generally the savings are around 40% over the whole parlour electricity cost. Varivac have single phase models to cover the whole range so really any parlour can have a Varivac now. http://www.rcapperdairy.co.uk/about-us.asp
Heat Recovery technology is being used successfully in many pasture based dairyfarms in the UK. Gavin in North Devon has installed Varivac & Heat Recovery units & reduced total farm demand by approx 20%. The next challenge is to install "smart technology" that allows the switching on & off of equipment when he can make full use of the wind. Tim in Shropshire has installed a heat recovery unit, solar water heating & Varivac systems. He has seen on his smart meter similar total farm saving. The Smart meter graph shows when the energy saving devices were installed.You can see the impact of the very cold weather last December when heating & hot water effectively doubled demand during milking. So it's up to you which generation option you chose but you also need to deal with reducing peak demand. See the blog I wrote on the 15th October 2010.Seek out the interest free loans
. Current UK Pasture Measurements
Mixed rainfall, most areas in the UK still dry, Wales coast good rain & growth. Cold temperatures & drying winds depressing effect of recent rain. SE England very dry & struggling for pasture.
TheAverage Pasture Cover (kgsDM/ha) & Pasture Growth (kgsDM/ha/day)
South Ayrshire, AFC 2349,Growth =Demand 68kgs, soil temp 9.9degrees C
Derbyshire, 2365, growth 80kgsDM/ha/day, Demand 64
Herefordshire, 2150, growth 55, Demand 60
Gloucestershire, 2073, growth 51, demand 50 Getting very dry
Pembrokeshire, 2041, growth 61, wedge has hole will feed silage
Sussex Organic, AFC 1481,growth 11kgs, Drying off early really need rain
East Sussex, 1900, growth 30, desparate for rain
North Devon, AFC 2350, 65kgs, some rain some recovery from dry
Limerick, Ireland, 2250, growth 70kgs
Fish Creek, Gippsland Victoria Australia (autumn) AFC 2550, growth 38, AFC increasing, unusually wet last of spring calvers being dried off.
It maybe of interest to you that this blog has been read by people in 58 different countries this month ...a truely international audience!